Chronograph or stop watch.



W. B. PORTER. 'OHRONOGRAPH OR STOP WATCH. APPLICATION FILED NOV. 7, 1911.

1 0 9 5 I Patented Mar. 10, 191 1 IIIIIIIIIIIIIIIIII COLUMBIA PLANOGRAPH CID-.WASHINGTUN. D c.

UNITED STATES PATENT OFFICE.

WILSON E. PORTER, OF NEW HAVEN, CONNECTICUT, ASSIG-NOR TO NEW HAVEN CLOCK 00., OF NEW HAVEN, CONNECTICUT, A CORPORATION.

CHRONOGBAPH OR STOP WATCH.

Application filed November 7, 1911.

To all whom it may concern:

Be it known that I, WILSON E. Ponrnn, a citizen of the United States, residing at New Haven, in the county of New Haven and State of Connecticut, have invented a new and useful Improvement in Chronograph or Stop VVat-ches; and I do hereby declare the following, when taken in connection with the accompanying drawings and the letters of reference marked thereon, to be a full, clear, and exact description of the same, and which said drawings constitute part of this specification, and represent, in

Figure 1 a view in rear elevation of a stop-watch movement constructed in accordance with my invention with its parts in the positions required of them for the operation of the sweep-second hand. Fig. 2 a corresponding view of the same. parts in the stopped position of the sweep-second hand. Fig. 3 a corresponding view showing the coaction of the fly-back lever with the heartcam for restoring the sweep-second hand to its zero position. Fig. 1 a detached broken inside view of the front movement-plate showing the push-pin for the operation of the chronograph mechanism. Fig. 5 a broken sectional view on an enlarged scale on the line ab of Fig. 1. Fig. 6 a detached view of the fly-back lever. Fig. 7 a detached view of the arbor-tilting lever.

My invention relates to an improvement in chronograph or stop-watches, the object being to produce a simple, convenient and reliable stop-watch constructed with particular reference to fewness and simplicity of parts and accuracy of performance in sto-pping and starting.

lVith these ends in view my invention consists in a stop-watch having certain details of construction and combinations of parts as will be hereinafter described and pointed out in the claims.

In carrying out my invention as herein shown, I locate the fly-back lever 2 upon the same center as the arbor-tilting lever 3 so that in all positions of these levers the restoring nose 1 of the fly-back lever will be on the same center as the heart-cam 5, whereby an accuracy of performance in stopping and starting not possible when the said levers turn on different centers as in the common practice, is assured. For the purpose described, the fly-back lever 2 is installed so as to oscillate upon a heavy stud 6 mounted Specification of Letters Patent.

Patented Mar. 10, 1914:.

Serial No. 658,929.

in the rear movement-plate 7 as clearly shown in Fig. 5, the outer end of the said stud being counterbored and threaded for the reception of a screw stud 8 on which the arbor-tilting lever 3 oscillates. The said arbor-tilting lever 3 forms a bearing for the inner end of the centrally arranged tilting sweep-second hand arbor 9 upon which the driven chronograph-wheel 10 is mounted. By tilting the said arbor 9, the said wheel 10 is meshed into and demeshed from the driv ing chronograph-wheel 11 which exactly corresponds to it in size and number of teeth, and is mounted upon the rear end of the arbor 12 of the fourth-wheel or pinion, so called, of the timennovement. I have chosen to designate the lever 3, the arbor-tilting lever, for the reason that one of its chief functions is to provide for tilting the arbor 9 as required to start and stop the driven chronograph-wheel 10 which by being so tilted by the said lever is brought into and out of contact with the driving chronographwheel 11 which is constantly driven by the time-movement of the watch. By the tilting of the arbor 9 and the wheel 10, I eliminate the intermediate wheel generally employed for transmitting the movement of the driving chronograph-wheel to the driven chronograph-wheel of chronograph watches.

In order that the sweepsecond hand arbor 9 may not be accidentally shifted after it has been stopped, I employ a light spring 13 which frictionally engages with the said arbor as shown in Fig. 5, and which is mounted in the inner end of a stud 14: carried by the arbor-tilting lever 3 and extending inward into the watch-movement through a slot or notch 15 in the plate 7. The said stud 1a is itself engaged by the end of an operating-spring 16 fastened at its opposite end to the inner face of the rear movement-plate 7 and exerting a constant effort to swing the arbor-tilting lever 23 so as to mesh the fine teeth of the driven chronograph-wheel 10 into the corresponding teeth of the driving chronograph-wheel 11. The said fly-back lever 2 is formed, at its outer end with a hook-like finger 17 and the outer end of the arbor-tilting lever with a corresponding finger 18, these fingers being differentiated in length so as to successively co-act with the three notches 19 of a castle-wheel 20 adjustably secured by a screw 21 to a shouldcred shaft 22 ournaled at one end in the rear movement-plate 7 and at its opposite end in the front movement-plate 23. The said shaft 22 has mounted upon it a ratchetwheel 24 engaged by a spring pawl 25 mounted in one end of a lever 26 swung at its opposite end upon one of the pillars 27 of the watch-movement, this lever 26 being engaged between its ends by a push-pin 28 which projects out-ward through the casering 29 at a point near the pendant of the watch. A spring 30 encircling the pillar 27 is arranged to exert a constant effort to throw the lever 26 outward against the push-pin 28, while a spring 31 mounted in the plate 23 engages with the teeth of the ratchet 2st so as to prevent the retrograde movement thereof by the dragging action of the spring pawl 25 when the lever 26 moves outward.

The sweep-second hand arbor 9 extends forward into a hollow stud 32 mounted in the center of the front movement plate 23 th extreme forward end of the arbor being reduced in diameter to form a pivot 33 which has rocking bearing in a bearingopening formed in the outer end of the hollow stud 82. its this bearing of the arbor 9 is located very near its extreme forward end, the swinging of the arbor by the arbor-tilting lever 3 to mesh and demesh the Wheels 10 and 11 does not appreciably disturb the position of the sweep-second hand which is not shown, but which is mounted upon the end of the said pivot 33. The driven minute-wheel with its hub 35 rotates upon the hollow stud 32, the projecting outer end of the hub 35 receiving the minute hand, and the wheel 34 being meshed into and driven by a corresponding driving min lite-wheel 36 mounted upon the center arbor 37 which is frictionally connected with the hollow center-shaft 38 which is jo-urnaled at its opposite ends in the plates 23 and 7. The hour-wheel 39 and its hub 40 revolve upon the said hub of the minute-wheel 3 the hour-wheel 39 meshing into and being driven by dial-pinion a1 located at th outer end of the center-arbor 37. The hollow center-shaft 38 carries a center-wheel 42 and center-pinion 4-3, these parts being herein given the names employed for their designation when they are located in the center of ordinary time movements. The watch under consideration being a stopwatch, the center-arbor and its related parts are located to one side to give free space for the sweep-second hand arbor and the parts associated therewith.

My improved stop-watch is operated in the usual manner by pushing its push-pin 22 inward, whereby the castle-wheel 20 is revolved step-by-step for the successive 0peration of the fly-back lever 2 and the arbortilting lever 3. As the operation of stopwatch castle-wheels is old and well understood, it seems unnecessary to detail the operation here of the said wheel and the action of the levers 2 and 3 thereby.

I claim 1. In a stopwvatch, the combination with a centrally arranged sweep-second hand arbor, of a heart-cam and a driven chronograph-wheel mounted thereupon, a fly-back lever co-acting directly with the said cam for rotating the said arbor as required to re store the sweep-second hand to its zero posi tion, an arbor-tilting lever forming a bear ing for one end of the said arbor and providing for the tilting thereof, a stud upon which both of the said levers are mounted for oscillation independent of each other, a fourth wheel or pinion arbor, a driving chronograph-wheel mounted upon the same and corresponding in size and number of teeth to the said driven chronograplrwheel and means for successively operating the said levers whereby the sweep-second hand arbor and driven chronograph-wheel are tilted for meshing the said wheel into and demeshing it from the said driving chronograph-wheel, and whereby the sweep-second hand arbor is rotated as required for the restoration of its sweep-second hand to its zero position when the said wheels are de meshed. Y

2. In a stop-watch, the combination with the time-train thereof, including a fourthwheel or pinion arbor, of a fly-back lever, an

arbor-tilting lever, a stud upon which both of the said levers are mounted for oscillation independently of each other, means for operating the said levers in succession, a sweep-secondhand arbor having its inner end mounted in the said arbor-tilting lever, a heart-cam, a driven chronograph-wheel mounted upon the inner end of the said sweep-secondhand arbor, a driving chronograph-wheel exactly corresponding in size to the said driven chronograph-wheel and meshing directly thereinto for driving the same, and demeshed therefrom by the tilting of the said arbor by the action of the said arbor tilting lever, a center-arbor located at one side of the center of the watch-movement, and dial-worl-z connecting the said center-arbor with hour and minute wheels concentric with the outer end of the said sweep-second-hand arbor.

In testimony whereof, I have signed this specification in the presence of two subscribing witnesses.

WILSON E. PORTER. Witnesses CLARA L. VVEED, Gnonen D. SEYMOUR.

Copies 03 this patent may be obtained. for five cents each, by addressing the Commissioner of Patents, Washington, D. G. 

